Perl MarkMail

Tim O'Reilly is raving about MarkMail, apparently a nifty way of
navigating large mailboxes, such as mailing list archives:
http://radar.oreilly.com/archives/2008/01/markmail_opensource_search.html
Perl is one of the projects whos archives are covered:
http://perl.markmail.org/
Anybody played with it?
It appears to be Flash-based, but I just get a large white space with a
small emblem flashing "loading...". I'm running Ubuntu 7.10; possibly
I'd've had more success if I'd opted to install Adobe's Flash player
rather than Gash when Firefox prompted (but now I've picked that it
isn't at all obvious how to change to the other one instead).
Smylers